chore(openclaw): add tsup build pipeline with ESM output and type declarations (#4335)

openclaw/tsup.config.ts

@@ -0,0 +1,9 @@
+import { defineConfig } from "tsup";
+
+export default defineConfig({
+  entry: ["index.ts"],
+  format: ["esm"],
+  dts: true,
+  sourcemap: true,
+  clean: true,
+});